In spatial scalable video coding, the source video frame sequence of an original video signal is encoded into a base layer bit-stream and an enhancement layer bit-stream. It is possible that the base layer bit-stream alone can be decoded to recover the source video frame sequence. Alternatively, both the base layer bit-stream and the enhancement layer bit-stream can be used together to recover the source video frame sequence with a resolution that is higher than the one recovered if the base layer bit-stream alone is used. Such feature is useful, for example, in video broadcasting over the Internet.
In implementation of a scalable video transmission system, it is highly desirable if the scalable video coding method is such that non-scalable encoders and/or decoders can be used (or reused) in the system. One advantage is to enable easy upgrade from a non-scalable video transmission system to the scalable one. In this situation, the scalable video transmission system can be implemented with a low degree of modification to existing hardware used in the original non-scalable system.
In US20120002726, a spatial scalable video encoding method that enables the use of non-scalable encoders is disclosed. It is desirable if non-scalable video decoders can be employed. In particular, it is advantageous if “legacy” non-scalable decoders compliant to published video standards can be reused. There is a need in the art for a scalable video coding method that allows the use of non-scalable video decoders.